Question 1

Which of the following best explains why sodium (Na) forms a cation while chlorine (Cl) forms an anion in the formation of NaCl?
Correct answer: Sodium loses electrons to achieve a stable octet, while chlorine gains electrons to achieve a stable octet.

Accepted Answer

Sodium loses electrons to achieve a stable octet, while chlorine gains electrons to achieve a stable octet.

Question 2

Which of the following molecules is expected to have the largest dipole moment?
Correct answer: HF

Accepted Answer

HF

Question 3

A student draws the Lewis dot symbol for the oxide ion (O2−). Which of the following is correct?
Correct answer: The symbol O with eight dots and a 2− charge.

Accepted Answer

The symbol O with eight dots and a 2− charge.

Question 4

Which of the following best describes metallic bonding in copper (Cu)?
Correct answer: Copper atoms are surrounded by a 'sea' of delocalized valence electrons.

Accepted Answer

Copper atoms are surrounded by a 'sea' of delocalized valence electrons.

Question 5

Which of the following statements about electronegativity is correct?
Correct answer: Electronegativity increases from left to right across a period and up a group.

Accepted Answer

Electronegativity increases from left to right across a period and up a group.

Question 6

Given the following Lewis structure for the nitrate ion (NO3−), what is the formal charge on the central nitrogen atom?

O=N(+)-O(−)-O(−)

Correct answer: 0

Accepted Answer

0

Question 7

Which of the following compounds contains a polar covalent bond?
Correct answer: HCl

Accepted Answer

HCl

Question 8

A molecule of carbon dioxide (CO2) is nonpolar even though it contains polar bonds. Why?
Correct answer: The molecule is linear, and the bond dipoles cancel each other out.

Accepted Answer

The molecule is linear, and the bond dipoles cancel each other out.

Question 9

Which of the following best describes the octet rule?
Correct answer: Main group elements tend to achieve eight valence electrons through bonding.

Accepted Answer

Main group elements tend to achieve eight valence electrons through bonding.

Question 10

Which of the following elements is most likely to violate the octet rule by having an expanded octet?
Correct answer: Phosphorus

Accepted Answer

Phosphorus

Question 11

Which of the following best explains why metals are good conductors of electricity?
Correct answer: Metals have free-flowing valence electrons that can move throughout the lattice.

Accepted Answer

Metals have free-flowing valence electrons that can move throughout the lattice.

Question 12

Which of the following pairs of atoms would form a bond with the greatest ionic character?
Correct answer: Na and Cl

Accepted Answer

Na and Cl

Question 13

A student is asked to draw the Lewis structure for the ammonium ion (NH4+). How many valence electrons should be included in the structure?
Correct answer: 8 (5 from N + 4 from H − 1 for the positive charge)

Accepted Answer

8 (5 from N + 4 from H − 1 for the positive charge)

Question 14

Which of the following statements about formal charge is correct?
Correct answer: Formal charge is calculated as the number of valence electrons minus the sum of nonbonding electrons and bonds.

Accepted Answer

Formal charge is calculated as the number of valence electrons minus the sum of nonbonding electrons and bonds.

Question 15

Which of the following best describes the bonding in a molecule of O2?
Correct answer: Nonpolar covalent bonding with equal sharing of electrons.

Accepted Answer

Nonpolar covalent bonding with equal sharing of electrons.

Question 16

Which of the following is the correct Lewis dot symbol for a magnesium ion (Mg2+)?
Correct answer: Mg with no dots and a 2+ charge

Accepted Answer

Mg with no dots and a 2+ charge

Question 17

Which of the following scenarios best illustrates the application of the octet rule in a real-world context?
Correct answer: The use of sodium chloride in intravenous saline solutions, where Na+ and Cl− ions are stabilized by achieving noble gas configurations.

Accepted Answer

The use of sodium chloride in intravenous saline solutions, where Na+ and Cl− ions are stabilized by achieving noble gas configurations.

Question 18

Which of the following best explains why water (H2O) has a bent molecular shape and a net dipole moment?
Correct answer: The two lone pairs on oxygen repel the hydrogen atoms, creating a bent shape and resulting in a net dipole.

Accepted Answer

The two lone pairs on oxygen repel the hydrogen atoms, creating a bent shape and resulting in a net dipole.

Question 19

Which of the following best describes the difference between polar covalent and nonpolar covalent bonds?
Correct answer: Polar covalent bonds involve unequal sharing of electrons due to differences in electronegativity, while nonpolar covalent bonds involve equal sharing.

Accepted Answer

Polar covalent bonds involve unequal sharing of electrons due to differences in electronegativity, while nonpolar covalent bonds involve equal sharing.

Question 20

Which of the following is a correct application of formal charge to determine the most stable Lewis structure for the sulfate ion $$(SO4^2$$−)?
Correct answer: The most stable structure minimizes formal charges, ideally placing negative charges on the more electronegative oxygen atoms.

Accepted Answer

The most stable structure minimizes formal charges, ideally placing negative charges on the more electronegative oxygen atoms.

Key Concepts in Chemical Bonding and Lewis Structures

Study Guide - Practice Questions

Study Guide - Flashcards